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		<title>three.js webgpu - custom fog background</title>
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			<a href="https://threejs.org/" target="_blank" rel="noopener" class="logo-link"></a>

			<div class="title-wrapper">
				<a href="https://threejs.org/" target="_blank" rel="noopener">three.js</a><span>Custom Fog Background</span>
			</div>

			<small>
				Custom Fog Background via Post-Processing.<br/>
				Battle Damaged Sci-fi Helmet by <a href="https://sketchfab.com/theblueturtle_" target="_blank" rel="noopener">theblueturtle_</a>.
				<a href="https://hdrihaven.com/hdri/?h=royal_esplanade" target="_blank" rel="noopener">Royal Esplanade</a> by <a href="https://hdrihaven.com/" target="_blank" rel="noopener">HDRI Haven</a>.
			</small>
		</div>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.webgpu.js",
					"three/webgpu": "../build/three.webgpu.js",
					"three/tsl": "../build/three.tsl.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three/webgpu';
			import { pass, color, rangeFogFactor } from 'three/tsl';

			import { UltraHDRLoader } from 'three/addons/loaders/UltraHDRLoader.js';

			import { OrbitControls } from 'three/addons/controls/OrbitControls.js';
			import { GLTFLoader } from 'three/addons/loaders/GLTFLoader.js';

			let camera, scene, renderer;
			let postProcessing;

			init();

			function init() {

				camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 0.25, 20 );
				camera.position.set( - 1.8, 0.6, 2.7 );

				scene = new THREE.Scene();

				renderer = new THREE.WebGPURenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.setAnimationLoop( animate );
				renderer.toneMapping = THREE.NoToneMapping; // apply tone mapping in post processing, instead
				document.body.appendChild( renderer.domElement );

				// post processing

				// render scene pass
				const scenePass = pass( scene, camera );
				const scenePassViewZ = scenePass.getViewZNode();

				// fog color
				const fogColor = color( 0x4080cc ); // in sRGB color space

				// get fog factor from the scene pass context
				// equivalent to: scene.fog = new THREE.Fog( 0x4080cc, 2.7, 4 );
				const fogFactor = rangeFogFactor( 2.7, 4 ).context( { getViewZ: () => scenePassViewZ } );

				// tone-mapped scene pass
				const scenePassTM = scenePass.toneMapping( THREE.ACESFilmicToneMapping, 1 );

				// mix fog using fog factor and fog color
				const compose = fogFactor.mix( scenePassTM, fogColor );

				postProcessing = new THREE.PostProcessing( renderer );
				postProcessing.outputColorTransform = true; // no tone mapping will be applied, only the default color space transform
				postProcessing.outputNode = compose;

				//

				new UltraHDRLoader()
					.setPath( 'textures/equirectangular/' )
					.load( 'royal_esplanade_2k.hdr.jpg', function ( texture ) {

						texture.mapping = THREE.EquirectangularReflectionMapping;
						scene.environment = texture;

						// model

						const loader = new GLTFLoader().setPath( 'models/gltf/DamagedHelmet/glTF/' );
						loader.load( 'DamagedHelmet.gltf', function ( gltf ) {

							scene.add( gltf.scene );

						} );

					} );

				//

				const controls = new OrbitControls( camera, renderer.domElement );
				controls.minDistance = 2;
				controls.maxDistance = 5;
				controls.target.set( 0, - 0.1, - 0.2 );
				controls.update();

				window.addEventListener( 'resize', onWindowResize );

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			//

			function animate() {

				postProcessing.render();

			}

		</script>

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